Intubation is the placement of a tube of an intubation device into an airway lumen of the body of a patient to provide assisted ventilation of the lungs to maintain a supply of oxygen to the blood in those cases where the patient is unable to breathe on his or her own. Intubation in cases of respiratory distress involves the placement of a tube into the trachea of the patient. Tracheal intubation also involves the positioning of an endotracheal tube into a patient's trachea through the vocal cords, so the caregiver must also be careful to avoid injuring the vocal cords. In many cases, care must be taken when intubating a patient since improper placement of the tube can result in additional harm to the patient. For example, many conventional intubation devices rely on an inflatable cuff that forms a seal against the lumen wall to maintain a position of the tube within the lumen. Over-inflation of the cuff, can cause internal bleeding in the patient. Another significant problem is that extreme care must be taken to avoid positioning the intubation tube within the esophagus rather than the trachea. In such cases, with conventional devices, the first responder or medical practitioner cannot properly ventilate the patient and the patient can suffer further injury.
Even properly trained medical caregivers and first responders must proceed with caution during intubation to avoid misplacement of the intubation device or to avoid unwanted insertion errors and risk of injury. Delay and/or misplacement of the endotracheal tube, such as misplacement of the endotracheal tube into the esophagus, can potentially result in neurological damage or death. Improper positioning of the endotracheal tube also can compromise airway protection or result in inadequate ventilation. It is therefore imperative to intubate a patient quickly and position the endotracheal tube correctly when a medical condition arises.
To reduce the risk of complications during intubation, the caregiver, whether a first responder, such as an emergency medical technician, paramedic, or a nurse or physician must proceed as quickly as possible yet with caution to avoid the potential complications. In addition, a first responder must often attempt to intubate the patient in a less than desirable location such as a bathroom, restaurant, or other area not conducive to providing proper medical treatment and care.
Assisted ventilation in cases of cardiac arrest also requires prompt and accurate placement of an intubation device within the trachea so that chest compressions can occur. In such cases, intubation allows for ventilation of the lungs and a supply of oxygen to the blood while chest compressions provide circulation of the blood.
The American Heart Association's protocols for cardio pulmonary resuscitation (CPR) previously required pausing after every fifteen chest compressions to allow for two ventilations. The American Heart Association's 2010 protocols decreased the frequency of ventilations such that chest compressions are to be paused after every thirty compressions to allow for two ventilations. It is believed that the main reasons supporting the change in protocol are: 1) reduce the amount of intra-thoracic pressure associated with positive pressure ventilations since positive pressure ventilations decrease the efficiency of the heart; and 2) to minimize the interruptions of chest compressions to maintain constant arterial pressure. Accordingly, now most caregivers only simultaneously ventilate the patient and provide compressions if the patient is properly intubated.
FIG. 1 provides a partial view of a patient's oral cavity 10, tongue 12 and pharynx 14 where the pharynx 14 is the membrane-lined cavity at the rear of the oral cavity 10. The pharynx 14 includes openings of the esophagus 16 and trachea 18. As shown, the openings to the esophagus 16 and trachea 18 are adjacent to one another. When a medical caregiver attempts to intubate a patient, the caregiver shall attempt to position the intubation device within the trachea 18 to provide oxygen to the lungs 2. As noted above, the caregiver shall attempt to avoid positioning the intubation device within the esophagus 16 and in doing so often must proceed slowly and with caution to avoid causing undesired trauma to vocal cords or other structures within the body.
The wall of the esophagus 16 is composed of striated and smooth muscle. Since the esophagus 16 relies on peristalsis to move food downward towards the stomach, the walls of the esophagus 16 are naturally compliant and do not have any structural reinforcement. The trachea 18, on the other hand, is relatively stronger and is naturally designed not to collapse given its function of transporting air to the bronchi and lungs 2. The wall of the trachea 18 includes a number of cartilaginous semicircular rings 20 that prevent the trachea 18 from collapsing. The trachea 20 lies anteriorly to the esophagus 16 where the openings of the esophagus 16 and trachea are separated by a tiny flap, the epiglottis 22. The epiglottis 22 protects the trachea when the individual swallows food or other substances.
FIG. 2 illustrates a conventional device 50 used for intubating a patient. As shown, the device 50 is inserted through the mouth and oral cavity into the trachea 18. The caregiver must navigate the device 50 into the trachea 18 rather than the esophagus while traversing the epiglottis 22 and vocal cords 24. The caregiver must take particular care to avoid causing damage to the vocal cords 24. Once properly positioned, the caregiver can optionally inflate 52 a balloon on the device 50 to anchor the device within the trachea 18. After the caregiver confirms placement of the device 50, ventilation of the patient can take place.
Presently, the Combitube, supplied by Nellcor, is commonly used for airway management. The Combitube, also known as a double-lumen airway, is a blind insertion airway device (BIAD) used by first responders as well as in an emergency room setting. The Combitube is intended to allow for tracheal intubation of a patient in respiratory distress by use of a cuffed, double-lumen tube. The double lumen tube is inserted into the patient's airway to allow for ventilation of the patient's lungs. Inflation of the cuff allows the device to function similarly to an endotracheal tube and usually closes off the esophagus, allowing ventilation and preventing pulmonary aspiration of gastric contents.
However, placement of traditional intubation devices is very difficult due to the risk of improperly positioning the device. The risk of a device being improperly positioned can be fatal if not recognized. The conventional devices described above require positioning by an individual that is well trained in positioning such devices. Furthermore, even well trained individuals must proceed with caution when placing conventional devices.
In addition, there remains a need to improve timing of air delivery during artificial ventilations of a patient. This need especially remains where the patient is experiencing distress and requires both ventilation for oxygen and chest compression to re-establish blood circulation. Presently, if the act of artificially ventilating the individual (e.g., through assisted ventilation or mouth-to-mouth) and providing chest compressions is not timed, such as during normal CPR, normal artificial ventilation of the individual can work against the effectiveness of the compression. For instance, assisted ventilation by repeatedly delivering a large bolus of air can raise the pressure within the thoracic cavity and increase resistance by raising pressure on the heart. This back pressure can prevent the heart and lungs from filling with blood. As a result, impeding the ability of the heart and lungs to fill with blood, makes the chest compression less effective as a lower volume of blood is circulated after the compression.
There remains a need for a ventilation device and/or system that can effectively ventilate individuals and can be effectively positioned with minimal training required by the caregiver. In addition, there remains a need for such ventilation devices and methods to optimize the effect of providing assisted ventilation with chest compressions to circulate oxygenated blood within an individual.